The Federal Emergency Management Agency (FEMA) is performing detailed coastal engineering analyses and mapping of the San Francisco Bay shoreline in accordance with FEMA’s February 2005 Pacific guidelines for new coastal studies which are included in Appendix D of the Guidelines and Specifications for Flood Hazard Mapping Partners within the nine counties of:
The San Francisco Bay Area Coastal Study includes both regional hydrodynamic and wave modeling of the San Francisco Bay, as well as detailed onshore coastal analysis used to estimate wave runup and overtopping, as well as overland wave propagation. These onshore analyses will form the basis for potential revisions to the Base Flood Elevations (BFEs) and Special Flood Hazard Areas (SFHAs) within the coastal areas.
The new coastal study will revise and update the flood and wave data based on current conditions within the coastal Flood Insurance Study reports and Flood Insurance Rate Maps for each of the nine counties. The study is progressing on a county-by-county schedule. For an estimate of the affected area and panels, click here.
FEMA’s coastal study and mapping efforts benefit from new technologies and coastal data, including the latest 2010 detailed topographic data collected by the USGS and NOAA. Studies by other entities, such as the US Army Corps of Engineers (USACE), will be evaluated for compatibility with FEMA’s study and mapping goals.
To stay up the date with the SF Bay Area Coastal Study, sign up for our quarterly bulletin, Coastal Beat that will include schedule updates, technical articles and facts of interest, as well as relevant information as the study progresses.
To download the San Francisco Bay Area Coastal Study brochure, click here.
To download the San Francisco Bay Area Coastal Study FAQ, click here.
Tidal Datums and Extreme Tide Elevations Report
FEMA, in collaboration with local and state agencies, has released a new report that provides enhanced information on tidal datums and extreme tide elevations along the entire San Francisco Bay shoreline. Download the report here.
Extreme Storms in San Francisco Bay - Past to Present
FEMA has released a new report that highlights three of the largest storm events that have impacted the Bay’s shoreline communities, and illustrates the extent of flooding that could happen if these storms occur again today. Download the report here.
New! Increased Flooding Scenario Maps
FEMA has created Increased Flooding Scenario Maps for the interior shoreline for all nine Bay Area counties. These new non-regulatory products complement the National Flood Insurance Program regulatory products, i.e. the Flood Insurance Rate Maps (FIRMs), Flood Insurance Study reports and GIS databases per County.
These maps utilize the most up-to-date coastal floodplain mapping data based on FEMA’s San Francisco Bay Area Coastal Study and provide additional information on how the 1-percent-annual-chance (i.e. 100-year) coastal floodplain may change with a 1-foot, 2-foot, and 3-foot increase in Bay water levels.
To see the slides that were presented via webinar to Bay Area communities on April 21, 2016, click here.
To download the Increased Flooding Scenario Maps brochure, click here.
To download the Increased Flooding Scenario Maps FAQ, click here.
To view the Increased Flooding Scenario Maps, use the following links:
To download GIS data for the Increased Flooding Scenario Maps, use the following links:
To download PDF mapbooks for the Increased Flooding Scenario Maps, use the following links: